Lock for temporary binders



J. K. SHUTTLEWORTH.

LOCK FOR TEMPORARY BINDERS.

APPLICATION FILED JUNE 17. 1920.

1,360,590. r Patented Now 30,1920- INVENTCIRQ ATT UNITED STATES JOHN K. SHUTTLEXVORTEI, OF TORONTO, ONTARIO, CANADA.

LOOK FOR TEMPORARY BINDERS.

Specification of Letters Patent. Patented N v 30 192(} Application filed June 17, 1820. Serial No. 389,638.

To all whom it may concern:

Be it. known that I, Jorrn K. SHUTTLE- won'rii. a subject of the King of Great Britain, of the city .of Toronto, in the county of York, Province of Ontario, Canada, have invented new and useful Improvements in Locks for Temporary Binders, of which the following is a specification.

This invention relates to temporary bind: ers used in loose-leaf bookkeeping systems to hold the leaves bound together for use.

In such binders for bank purposesitis often necesasry to provide means whereby it is impossible, or at least impossible without detection, to withdraw sheets from or place new sheets in the binder.

lVhile high grade locks have been employed more or less for this purpose, a plan which has met with. more general favor is to use a comparatively simple key lock and to provide means for positioning a seal slip of paper over the key hole so that the key cannot be inserted without puncturing the seal slip.

This arrangement is employed in a binder now on the market in which the seal strip overlies the key hole of the lock and is itself covered by a slidable plate also provided with a keyhole. which, when the device is locked. is in alinement with the stationary key hole. This slidable plate normally prevents the seal slip being removed and is locked in its protective position by a latch releasable by the key inserted through the key holes to unlock the binder. As long therefore as the sliding plate is in its protective position, the binder cannot be unlocked without destroying the seal so that any unauthorized tampering with the lock is easily detected. 7

I have found, however, that as the locks are ordinarily constructed it is a very simple matter to release the lock of the sliding plate and, after the plate is slid back, the seal strip is easily removed and may thereafter be replaced so that it is impossible to tell that the lock has been tampered with. Once the sealing strip has been removed, releasing the latch of the binder lock presents no dii'liculty. (lwing to the ease with which the protective seal can be removed and replaced, as I have demonstrated. the security of the binder against unlawful tampering entirely disappears and any firm or corporation relying on it is dwelling in false security.

Having the above conditions in mind, my

showing ments;

Fig. 2e. plan view 'of the under side of the top of the lock;

Fig. 3 a longitudinal section on the a-a in Fig. 2; and

Fig. 4: a longitudinal section of a modified form of the sliding plate.

In the drawings like numerals of reference indicate corresponding parts in the different figures.

1 is the plate which forms the cover of the lock, which plate has an opening 2 formed therein. Beneath the plate 1 is located a plate 3 having a keyhole l formed therein, preferably approximately centrally of the opening 2. Between the two plates the plate 5 is slidably supported. This plate is provided with akeyhole 6, which when the plate is in normal position is in substantial alinement with the keyhole 4.

7 is a spring secured to the plate 3 and enline . gaging a projection 8 on the slidable plate 5. Thls spring tends to move the plate 5 from its position with the key holes in alinement. 9 is a spring actuated latch which engages the projection 10 on the plate 5 to retain it against the pressure of the spring 7, with the key holes in alinement. As these locks are ordinarily constructed, the end of the latch 9 can he reached by a thin metal hook inserted between the plates 1 and 5,

whereby the latch an be unlocked. To provent this I form on the plate 5 an extension 11 which extends sufficiently far beyond the projection 10 to prevent any book being en gaged with the end of the latch 9. Further protection, is given by forming a lip,wpreferably downwardly at the forward end of the extension 11. This device I find to be very effective and adapted to make the looking means for the slidable plate 5 absolutely unpickable.

When the binder is looked a paper strip 12 forming a seal lies between the plate 3 and the slidable plate 5, completely closing the a. lockprovided with my'improvekey hole at. No key can then be inserted through the key holes 6 and 4 without breaking the seal. As with my improvements this sliding plate cannot be unlatched, the lock is made as safe as it was originally intended to be. .Vhen the binder is being unlocked, a key inserted through the keyholes also engages the latch 9 and releases it at the same time that it unlocks the lock proper of the binder, which is not shown.

In Fig. i the edge of the plate is shown 7 provided with an upwardly and rearwardly directed hook on the edge 13, which in a measure answers the purpose of the extension 11, though this construction is not quite so effective as the other.

lVhat I claim as my invention is 1, In a temporary binder the combination oi a lock cover having an opening therein; a keyhole plate underlying the cover having a keyhole therein normally exposed through the opening in the cover plate; a plate slidable between the cover plate and the keyhole plate having a keyhole formed therein adapted to be alined with the keyhole in the keyhole plate; a latch located below the keyhole plate and releasable by a key inserted through the keyhole; a projection on the slidable plate engageable by the latch to releasably retain the slidable plate with its keyhole in alinement with the keyhole in the keyholeplate; the keyhole plate having an opening'therein in which the projection opcrates when the plate slides; and means on the slidable plate, adjacent the projection, to guard the latch from engagement by a lock picking tool.

.2. In a temporary binder constructed as set forth in claim 1 in which the latch guard comprises an extension of the plate beyond the latch engaging projection. 1

Signed at Toronto this 1th day of June i J GEN K. SHUTTLEWORTH. 

